Counting leukocytes from whole blood using a lab-on-a-chip Coulter counter

• Published in: 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society 2012-01, Vol.2012, p.6277-6280
• Main Authors: Zhe Mei, Sung Hwan Cho, Zhang, Arthur, Jie Dai, Tsung-Feng Wu, Yu-Hwa Lo
• Format: Article
• Language: English
• Subjects: Blood; Electrodes; Impedance; Lab-on-a-chip; Microfluidics; Radiation detectors; USA Councils
• ISSN: 1094-687X; 1558-4615; 2694-0604
• DOI: 10.1109/EMBC.2012.6347429

A microfluidic lab-on-a-chip Coulter counter was demonstrated to count micro particles and leukocytes from whole blood. Instead of electroplated or deposited metal electrodes, off-the-shelf gold pins were used as electrodes to simplify fabrication process, reduce cost, enhance device durability, and above all, achieve superior uniformity in E-field distribution for improved signal quality. A custom-designed, low-cost demodulation circuit was developed to detect the AC impedance signals of the particles and cells passing the detection area defined by the microfluidic channels. A mixture of polystyrene beads with three different sizes was used to characterize the device. The results showed high throughput at 2000 particles/s and clear separation among different sizes of beads with coefficients of variation (CV) of 13.53%, 10.35% and 5.67% for 7.66μm, 10.5μm and 14.7μmbeads, respectively. To demonstrate the potential for a point-of-care or self-administered device for cancer patients going through chemotherapy, we have used the lab-on-a-chip device to count leukocytes from whole blood, generating encouraging preliminary results comparable to the results from a commercial flow cytometer.